I have never posted on the Solidworks forum before, but I am a fairly experienced SW user, currently using Solidworks 2014. I have exhausted all of the settings or features I can possibly find that could be causing the problem, but nothing will prevent it from occuring. Essentially I have set a custom scene, custom document properties, and a custom part appearance for this file. Except for the part appearance itself, I use these settings for all of my parts and assemblies and have not encountered the problem before. The normal, accurate appearance of my part looks like this:
It's supposed to appear dark gray, but clearly distinguishable from black. There is also some texture on the part. The yellow faces are a flat color and are not affected by this issue. However, the appearance will randomly become noticeably darker. The most repeatable way to make this happen I have found is to save the part. Even if no changes have been made at all (no star next to the filename) - I just load up the part appearing like the above image, then immediately hit save - the appearance will usually change to the following:
It's a little less noticeable and, of course, I shrunk the image to avoid taking up an immense amount of space. However, if you look at both you should notice the difference. I have noticed on a couple occasions this change NOT occurring when I save as I described. It also tends to occur in an assembly if I modify another part in any way, or in either the part or assembly if I modify any feature on the part. Most actions in the program will cause it to happen. I have also noticed that when I hover my mouse over the application bar at the bottom of windows, the preview will show a shaded background, as if it is darker. This could be consistent with the darker appearance on the part. Again, I have triple checked that there are no scene, environment, appearance, etc., settings any different before and after this occurs. Here is the background I described:
It actually appears to me as if the color of the part is closer to the correct one, while there is some shading that is like the "phantom" appearance. I have also searched for any similar question on the forum, with no luck. I am thinking this may just be a bug with some particular combination of features I applied, but tweaking it hasn't made it go away either. Any ideas what I may be doing wrong or need to take a look at?